The present invention relates to a composition and a method for the treatment and prevention of adhesions, and for the promotion of wound healing, and, more particularly, to a composition and a method for the treatment and prevention of pathological processes associated with wound healing, such as the formation of adhesions within the abdominal-pelvic cavity.
Wound healing is a complex process involving such factors as cells, extracellular matrix (ECM) components and the cellular microenvironment. Essentially, all wound healing involves the repair or replacement of damaged tissues. The precise nature of such repair or replacement depends upon the tissues involved, although all such processes involve certain basic principles. To illustrate these principles, cutaneous, or skin, wound healing will be described, it being understood that the discussion could also extend to all types of wound repair.
Skin has three layers, keratin, epidermis and dermis. If only the epidermis is damaged, as in most minor injuries, keratinocytes migrate from the edge of wound and eventually cover it, reforming the epidermis and keratin [D. R. Knighton and V. D. Fiegel, Invest. Radiol., Vol 26, p 604-611, 1991]. The risk of scar formation is thus relatively low for such minor injuries.
If all three skin layers are damaged or destroyed, new connective tissue, called granulation tissue, must first fill the wound space. This tissue is formed by deposition of ECM components by fibroblasts, which migrate into the wound space [D. R. Knighton and V. D. Fiegel, Invest Radiol., Vol 26, p. 604-611, 1991]. Although the formation of granulation tissue is clearly an important protective mechanism, it can also lead to the formation of scars. Production of ECM components, such as collagen, has been particularly linked to scar formation. Scars on the skin can be both a cosmetic and a functional problem. For example, scar formation following serious burns can restrict the nobility of joints. Scar formation within other types of tissue, such as in the lungs after a bacterial infection, or in many organ tissues following surgery, can be extremely dangerous. One reason scars within organ tissues are so dangerous is that the scar does not duplicate the functionality of the original organ tissue, so that the healing of the wound does not lead to a complete restoration of organ capacity and function. Thus, clearly scar formation can be a pathological process.
However, the deposition of ECM components, such as collagen, is currently believed to also be important for healing of the wound. Indeed, the prior art teaches that the strength of the healing wound is ultimately dependent upon collagen deposition [Haukipuro, K., et al., Ann. Surg., Vol 213, p. 75-80, 1991]. Thus, according to the prior art, collagen deposition must be present at a sufficient level to give the healing wound strength and support, yet not at such a high level to cause the formation of scars.
Another pathological process involved in the repair of damaged tissue is the formation of adhesions. The formation of adhesions between organs of the abdominal or pelvic cavities is a frequent and undesirable complication of abdomino-pelvic surgery. Surgical trauma to the tissue causes the release of a serosanguinous exudate, which forms a fibrous bridge that persists over the 4-5 days required for remesothelialization [Hill-West, J. L., et al., Obstet. Gynecol., Vol 83, p. 59-64, 1994; Sawhney, A. S., et al., Macromolecules, Vol 26, p. 581-587, 1993]. If the exudate is not absorbed or lysed within this period, it becomes ingrown with fibroblasts. Subsequent collagen production and deposition from these fibroblasts directly causes the formation of permanent scar tissue, which can connect the traumatized tissue to another organ, for example [Mahadevan et al., Fertil. Steril., Vol 44, p. 489-92, 1985]. Such permanent scar tissue is called an adhesion. Adhesions may be classified as either acquired (90%) or congenital (10%). The acquired type of adhesion is farther classified into inflammatory or post surgical, the majority being post surgical.
Hereinafter, the term xe2x80x9cabdominal adhesionxe2x80x9d will include adhesions in both the abdominal and pelvic cavities.
For example, patients undergoing multiple abdominal surgeries can have adhesion rates of up to 93% [Weibel, M. A. and G. Manjo, Am. J. Surg., Vol 126, p. 345-353, 1973]. Post-operative adhesions occur in 60-90% of patients undergoing major gynecological surgery [Monk, B. J. et al., Am. J. Obstet. Gynecol., Vol. 170, p. 1396-1403, 1994]. Thus, adhesions occur at an extremely high rate in patients who have undergone surgery in the abdominal area.
Adhesions can cause a number of further complications, such as intestinal obstruction. About 30-60% of patients who develop intestinal obstructions due to adhesions will require surgery, and a further 11-21% will develop recurrent obstructions [Menzies, D., Ann. Royal Col. Surg. Engl., Vol 75, p. 147-153, 1993]. Thus, these complications are serious and require substantial further treatment, thereby increasing both the trauma to the patient and the cost of the surgery. Indeed, in one surgical unit, 1% of all surgical admissions and 3% of all laparotomies were required for treatment of adhesions [Menzies, D., Ann. Royal Col. Surg. Engl., Vol 75, p. 147-153, 1993]. Furthermore, the frequency of intestinal obstructions caused by adhesions has increased steadily, from 7% in 1932 to about 60% in 1993[Vick, R. M., Br. Med. J., Vol 2, p. 546-548, 1932; Menzies, D., An. Royal Col. Surg. Engl., Vol 75, p. 147-153, 1993]. Thus, clearly the problem of adhesion-related complications is growing and methods for treating and preventing adhesions are clearly needed.
Other adhesion-related complications which can arise after pelvic surgery include chronic pelvic pain, voiding dysfunction and infertility [Monk, J. B. et al., Am. J. Obstet. Gynecol., Vol. 170, p. 1396-1403, 1994]. Adhesions can also arise from pelvic inflammatory disease, which is an important cause of infertility [Monk, J. B. et al., Am. J. Obstet. Gynecol., Vol. 170, p. 1396-1403, 1994]. Drugs such as cyclosporine can also cause adhesions and retroperitoneal fibrosis [D. M. Davies, ed., Textbook of Adverse Drug Reactions, Third Edition, Oxford University Press]. Thus, adhesions have many causes and can have serious and far-ranging consequences.
Unfortunately, no currently available method of treating and preventing adhesions is successful, particularly for blocking the mechanism of adhesion formation. For example, povidone-iodine was found to reduce the number of peritoneal adhesions after surgery by 35% in rats, but this effect was due to an anti-microbial effect, rather than a direct inhibition of adhesion formation [Gilmore, O. J. A. and C. Reid, J. Surg. Res., p. 477-481, 1978]. Another drug, dextran, was used by gynecological surgeons for adhesive prevention in infertility surgery but with little success [Holtz, G. et al., Fertil. Steril., Vol 33, p. 660, 1980]. Other compounds which have been tried include various plasminogen activators and fibrinolytic agents. These compounds were used because of the known fibrinolytic property of the peritoneum, resulting from the production of plasminogen activator. This production is reduced following trauma to the peritoneum, which may allow fibrin to form adhesions between traumatized areas [Raferty, A. T., Eur. Surg. Res., Vol 13, p. 397-401, 1981]. However, attempts to block fibrin deposition by using plasminogen activators and/or fibrinolytic agents has not proved routinely successful in rats, although some success was reported in rabbits [Rivkind, A. I., et al., Eur. Surg. Res., Vol 17, p. 254-258, 1985; Menzies, D. and H. Ellis, J. R. Soc. Med., Vol 82, p. 534-553, 1989]. Thus, currently available pharmacological methods are clearly not completely successful for the treatment or prevention of adhesions.
Non-pharmacological methods which have been tried include the use of polymeric or biological mechanical barriers to isolate a traumatized region from surrounding organs and other peritoneal tissues. However, these barriers have only had limited success in animal models [Sawhney, A. S., et al., J. Biomed. Mater. Res., Vol 28, p. 831-838, 1994; Sawhney, A. S., et al., Macromolecules, Vol 26, p. 581-587, 1993]. Furthermore, barrier methods have the disadvantage of requiring direct internal application to the site of trauma, rather than allowing systemic application.
As noted above, collagen deposition is an important step in the mechanism of adhesion formation, as well as in scar formation. If collagen deposition were prevented, adhesions and permanent scars might not be formed. Thus, these pathological processes are caused, at least in part, by the synthesis of excess collagen. Furthermore, the crucial role of collagen in other clinical conditions, such as fibrosis, has prompted attempts to develop drugs that inhibit its accumulation [K. I. Kivirikko, Annals of Medicine, Vol. 25, pp. 113-126 (1993)].
Such drugs can act by modulating the synthesis of the procollagen polypeptide chains, or by inhibiting specific post-translational events, which will lead either to reduced formation of extra-cellular collagen fibers or to an accumulation of fibers with altered properties. Unfortunately, only a few inhibitors of collagen synthesis are available, despite the importance of this protein in sustaining tissue integrity and its involvement in various disorders.
For example, cytotoxic drugs have been used in an attempt to slow the proliferation of collagen-producing fibroblasts [J. A. Casas, et al., Ann. Rhem. Dis., Vol. 46, p. 763 (1987)], such as colchicine, which slows collagen secretion into the extracellular matrix [D. Kershenobich, et al., N. Engl. J. Med., Vol. 318, p. 1709 (1988)], as well as inhibitors of key collagen metabolism enzymes [K. Karvonen, et al., J. Biol Chem., Vol. 265, p. 8414 (1990); C. J. Cunliffe, et al., J. Med. Chem., Vol. 35, p.2652 (1992)]. Unfortunately, none of these inhibitors are collagen-type specific. Also, there are serious concerns about the toxic consequences of interfering with biosynthesis of other vital collagenous molecules, such as Clq in the classical complement pathway, acetylcholine esterase of the neuro-muscular junction endplate, conglutinin and pulmonary surfactant apoprotein.
Certain other drugs which can inhibit collagen synthesis, such as nifedipine and phenytoin, inhibit synthesis of other proteins as well, thereby non-specifically blocking the collagen biosynthetic pathway [T. Salo, et al. J. Oral Pathol. Med., Vol. 19, p. 404 (1990)]. Even a drug which was relatively more specific for collagen synthesis, cianidanol, proved to be toxic because of its effects on the synthesis of many types of collagen and because of its effect on other Fe++ ion-binding enzymes, in spite of its ability to decrease the number of post-surgical adhesions in rats [Rivkind, A. I., et al., Arch. Surg. Vol 118, p. 1431-1433, 1983]. Thus, simply preventing adhesion formation alone does not make a compound useful if it is sufficiently non-specific to cause toxic side effects.
Collagen cross-linking inhibitors, such as xcex2-amino-propionitrile, are also non-specific, although they can serve as useful anti-fibrotic agents. Their prolonged use causes lathritic syndrome and interferes with elastogenesis, since elastic, another fibrous connective tissue protein, is also cross-linking. In addition, the collagen cross-linking inhibitory effect is secondary, and collagen overproduction has to precede its degradation by collagenase. Thus, a type-specific inhibitor of the synthesis of collagen itself is clearly required as an anti-fibrotic agent.
Such a type-specific collagen synthesis inhibitor was found by observing chickens which were fed extremely high levels of the coccidostat Halofuginone. These chickens were found to have fragile, weakened skin, as evidenced by increased skin tearing, which was caused by the inhibition of collagen synthesis [Granot, I. et al., Poultry Sci., Vol 70, p. 1559-1563, 1991]. Halofuginone and related compounds are disclosed in U.S. Pat. No. 5,449,678 for the treatment of a fibrotic condition, as a composition with a pharmaceutically effective amount of a pharmaceutically active compound of a formula: 
wherein:
n is 1 or 2
R1 is a member of the group consisting of hydrogen, halogen, nitro, benzo, lower alkyl, phenyl and lower alkoxy;
R2 is a member of the group consisting of hydroxy, acetoxy and lower alkoxy, and
R3 is a member of the group consisting of hydrogen and lower alkenoxy-carbonyl.
Of this group of compounds, Halofuginone has been found to be particularly effective for such treatment.
U.S. Pat. No. 5,449,678 discloses that these compounds are effective in the treatment of fibrotic conditions such as scleroderma and GVHD. WO No. 96/06616 further discloses that these compounds are effective for the treatment of restinosis, as they prevent vascular smooth muscle cell proliferation. Furthermore, Halofuginone has been shown to be effective in the prevention of adhesions between a surgically traumatized tendon and its sheath in chickens [Nyska, M. et al., Conn. Tissue Res., Vol 34, p. 97-103, 1996]. However, none of these studied models adequately predicts the behavior of Halofuginone in the promotion of wound healing or the prevention of abdominal adhesions for a number of reasons.
First, the prior art teaches against the use of Halofuginone to promote wound healing, since as described above, the prior art teaches that collagen is necessary for wound healing. According to the prior art, collagen is particularly necessary for the strength of the wound. Thus, any use of Halofuginone to reduce or prevent scar formation might be expected to also prevent the healing of the wound.
Second, the prior art does not teach the efficacy of Halofuginone in the treatment or inhibition of adhesions, since tendons and abdominal tissues have very different structures and compositions. Tendons are mainly collagen. When a tendon is damaged, new collagen synthesis must take place for the tendon to be repaired. It is easy to see how excess collages deposition could lead to the formation of adhesions between the tendon and its sheath, since such excess deposition could simply be the result of a slight oversynthesis of collagen during the repair of the tendon. Thus, inhibition of collagen synthesis should be expected to prevent the attachment of the tendon to its sheath.
By contrast, abdominal tissue has multiple layers. These layers include many different types of cells. However, none of these cells normally synthesize collagen. Instead, the mechanism of adhesion formation requires a complex interaction between fibrin, fibroblasts and the tissue of the peritoneum. It is not obvious that simply inhibiting one portion of this interaction would be successful in preventing the formation of adhesions, since this was tried with plasminogen activators and fibrolytic agents, as described above. These compounds also inhibit one portion of the mechanism of adhesion formation, yet they were not fully successful in preventing such formation. Such lack of success is particularly surprising since these compounds inhibit a relatively early stage in the process, where the chance of success might be considered comparatively greater. Thus, the mere inhibition of one step of adhesion formation does not appear to be sufficient to prevent such formation, or the related complications such as intestinal obstruction.
Next, the involvement of collagen type I in the formation of abdominal adhesions has not been previously demonstrated in the prior art. However, Halofuginone only inhibits the synthesis of collagen type I, and does not inhibit the synthesis of other collagens, such as xcex12(I), type II, type III or type X [Granot, I. et al., Biochim. Biophys. Acta., Vol 1156, p. 107-112, 1993; Choi, E. T. et al., Arch. Surg., Vol 130, p. 257-261, 1995]. Thus, the ability of Halofuginone to prevent the formation of abdominal adhesions cannot be predicted from the prior art, since such adhesions could have arisen from any one of these different types of collagen.
Finally, the route of administration in the study of Nyska et al. in chickens [Nyska, M. et al., Conn. Tissue Res., Vol 34, p. 97-103, 1996] involves tendons that were locally treated with Halofuginone through a catheter. Similarly, the barrier methods described above also require the direct administration of the barrier compound at the adhesion site. However, such a route makes treatment with Halofuginone impractical, since the treatment can then only occur during a surgical intervention. For certain types of adhesions, such as those caused by pelvic inflammatory disease, surgical intervention is not necessarily desirable. By contrast, much more efficient routes of administration would include systemic treatment, for example oral or parenteral administration. Such routes would permit treatment without any prior surgical intervention, as well as both pre- and post-operative treatment with Halofuginone, which could be particularly critical if complications develop substantially after surgery. Furthermore, systemic treatment should reduce of eliminate the need for further surgical intervention, which is not necessarily true for barrier or barrier-like methods of treatment.
There is thus a widely recognized need for, and it would be highly advantageous to have, a promoter of wound healing which substantially inhibits such pathological processes as adhesion formation, which can be administered pre- or post-operatively, or both, or substantially without prior surgical intervention, and which substantially prevents or reduces the formation of scars in the skin and other organs, as well as the formation of adhesions within the abdomen, particularly following surgical insult to tissue in the abdominal cavity, without causing non-specific effects.
According to the present invention, there is provided a composition and a method for treating an adhesion, the composition including a pharmaceutically effective amount of a compound in combination with a pharmaceutically acceptable carrier, the compound being a member of a group having a formula: 
wherein:
n is 1 or 2;
R1 is a member of the group consisting of hydrogen, halogen, nitro, benzo, lower alkyl, phenyl, and lower alkoxy;
R2 is a member of the group consisting of hydroxy, acetoxy, and lower alkoxy, and
R3 is a member of the group consisting of hydrogen and lower alkenoxy-carbonyl.
According to another embodiment of the present invention, there is provided a method of manufacturing a medicament for treating an adhesion, including the step of placing a pharmaceutically effective amount of a compound in a pharmaceutically acceptable carrier, the compound being a member of a group having a formula: 
wherein:
n is 1 or 2;
R1 is a member of the group consisting of hydrogen, halogen, nitro, benzo, lower alkyl, phenyl, and lower alkoxy;
R2 is a member of the group consisting of hydroxy, acetoxy, and lower alkoxy, and
R3 is a member of the group consisting of hydrogen and lower alkenoxy-carbonyl.
According to still another embodiment of the present invention, there is provided a method of manufacturing a medicament for substantially inhibiting formation of an adhesion, including the step of placing a pharmaceutically effective amount of a compound in a pharmaceutically acceptable carrier, the compound being a member of a group having a formula: 
wherein:
n is 1 or 2;
R1 is a member of the group consisting of hydrogen, halogen, nitro, benzo, lower alkyl, phenyl, and lower alkoxy;
R2 is a member of the group consisting of hydroxy, acetoxy, and lower alkoxy, and
R3 is a member of the group consisting of hydrogen and lower alkenoxy-carbonyl.
According to still another embodiment of the present invention, there is provided a method and a composition for substantially preventing formation of an adhesion, including the step of administering a pharmaceutically effective amount of a compound having a formula: 
wherein:
n is 1 or 2;
R1 is a member of the group consisting of hydrogen, halogen, nitro, benzo, lower alkyl, phenyl, and lower alkoxy;
R2 is a member of the group consisting of hydroxy, acetoxy and lower alkoxy, and
R3 is a member of the group consisting of hydrogen and lower alkenoxy-carbonyl.
According to other embodiments of the present invention, there is provided a method of manufacturing a medicament for treatment substantially before a performance of a surgical procedure for inhibition of formation of an adhesion, including the step of placing a pharmaceutically effective amount of a compound in a pharmaceutically acceptable carrier, the compound being a member of a group having a formula: 
wherein:
n is 1 or 2;
R1 is a member of the group consisting of hydrogen, halogen, nitro, benzo, lower alkyl, phenyl, and lower alkoxy;
R2 is a member of the group consisting of hydroxy, acetoxy, and lower alkoxy, and
R3 is a member of the group consisting of hydrogen and lower alkenoxy-carbonyl.
According to still other embodiments of the present invention, there is provided a composition for treatment substantially before a performance of a surgical procedure for inhibition of formation of an adhesion, including a pharmaceutically effective amount of a compound having a formula: 
wherein:
n is 1 or 2;
R1 is a member of the group consisting of hydrogen, halogen, nitro, benzo, lower alkyl, phenyl, and lower alkoxy;
R2 is a member of the group consisting of hydroxy, acetoxy and lower alkoxy, and
R3 is a member of the group consisting of hydrogen and lower alkenoxy-carbonyl.
A method of use of this composition is also provided
According to still other embodiments of the present invention, there is provided a method of manufacturing a medicament for treatment of an inflammatory disease characterized by formation of an adhesion, including the step of placing a pharmaceutically effective amount of a compound in a pharmaceutically acceptable carrier, the compound being a member of a group having a formula: 
wherein
n is 1 or 2;
R1 is a member of the group consisting of hydrogen, halogen, nitro, benzo, lower alkyl, phenyl, and lower alkoxy;
R2 is a member of the group consisting of hydroxy, acetoxy, and lower alkoxy, and
R3 is a member of the group consisting of hydrogen and lower alkenoxy-carbonyl.
According to yet another embodiment of the present invention, there is provided a composition for treatment of an inflammatory disease characterized by formation of an adhesion, including a pharmaceutically effective amount of a compound having a formula: 
wherein:
n is 1 or 2
R1 is a member of the group consisting of hydrogen, halogen, nitro, benzo, lower alkyl, phenyl, and lower alkoxy;
R2 is a member of the group consisting of hydroxy, acetoxy and lower alkoxy, and
R3 is a member of the group consisting of hydrogen and lower alkenoxy-carbonyl.
There is also provided a method of use of the composition. Preferably, the inflammatory disease in each of the above embodiments is pelvic inflammatory disease.
According to yet another embodiment of the present invention, there is provided a method of manufacturing a medicament for treatment of an inflammatory disease characterized by formation of an adhesion, including the step of placing a pharmaceutically effective amount of an antibiotic with a pharmaceutically effective amount of a second compound in a pharmaceutically acceptable carrier, the second compound being a member of a group having a formula: 
wherein:
n is 1 or 2;
R1 is a member of the group consisting of hydrogen, halogen, nitro, benzo, lower alkyl, phenyl, and lower alkoxy;
R2 is a member of the group consisting of hydroxy, acetoxy, and lower alkoxy, and
R3 is a member of the group consisting of hydrogen and lower alkenoxy-carbonyl.
There is also provided a composition for treatment of an inflammatory disease characterized by formation of an adhesion, including a pharmaceutically effective amount of an antibiotic and a pharmaceutically effective amount of a second compound having a formula: 
wherein:
n is 1 or 2;
R1 is a member of the group consisting of hydrogen, halogen, nitro, benzo, lower alkyl, phenyl, and lower alkoxy;
R2 is a member of the group consisting of hydroxy, acetoxy and lower alkoxy, and
R3 is a member of the group consisting of hydrogen and lower alkenoxy-carbonyl.
There is also provided a method of use of the composition. Again, preferably in each of the above embodiments, the inflammatory disease is pelvic inflammatory disease.